[FFmpeg-devel] threadmessage improvements v2

[Clément Bœsch]

Improvements & changes regarding last iteration:

[PATCH 1/3] avutil/threadmessage: add av_thread_message_flush()

- the flushing function can be set through a dedicated function instead of a
  new constructor prototype
- the flush function is now fixed regarding messages larger than a pointer...

[PATCH 2/3] fate/api: test threadmessage

- the test program is greatly improved by allowing multiple readers in addition
  to multiple senders.
- the flush now occurs randomly in readers and senders
- the messages are now larger than a pointer (see bug fix in 1/3) with a magic
  check

[PATCH 3/3] avutil/threadmessage: fix condition broadcasting

- instead of an inefficient wide signal broadcasting, it's now using 2 distinct
  conditions for reading and sending